This invention relates to solenoid valves for liquid and gaseous fluids wherein the valve member can be actuated by means of a plunger which is moveable relative to the valve seat and is located in the magnetic field of an electromagnet.
In known forms of solenoid valves of this type a diaphragm is disposed relative to a main valve seat for controlling the flow of fluid through the valve, being aided in its closing and opening actions by the fluid under pressure being controlled by the valve. In such an arrangement a pilot valve is often typically used to open or close an orifice through the diaphragm itself to achieve the necessary differential fluid pressures for control of the position of the diaphragm and which pilot valve opening is selectively opened and closed by the moving plunger of the electromagnetic coil assembly. In arrangements of this type the pilot valve is controlled by an elastomeric valve disc supported in a disc holder which receives its actuation from the moveable plunger. Spring means are provided for return movement of the disc holder and its assembly to a normally inactivated position while a second spring acting between the valve body and the diaphragm assembly serves to urge the latter also to a normally open position. The springs are selected in order to obtain a proper operating characteristic for the valve assembly and it is apparent with a great number of components involved that assembly procedures for the valve structure are difficult and complicated and subject to misassembly at high production levels.
An object of the present invention is to provide an improved solenoid valve assembly which is more readily assemblable than prior art designs and which is less subject to misassembled components.
Another object of the present invention is to provide a solenoid valve which exhibits a more reliable action valving at different pressure levels than prior art designs and which includes improved constructional characteristics.